Electrochemical sensors may be used for a wide variety of purposes. Carbon monoxide (CO) sensors, for example, may be used to help detect unsafe levels of carbon monoxide (CO) in a home or garage, for example. Carbon monoxide (CO) sensors may also be used for flue gas analysis in an environment where both carbon monoxide (CO) and hydrogen (H2) may be present. Carbon monoxide (CO) sensors that use a measuring electrode of platinum black (Pt), however, also respond to hydrogen (H2) and therefore may falsely identify the presence of carbon monoxide (CO).